The topics of this project are to study the chemical, immunological and biological properties of gonadotropins in tissues and biological fluids of normal subjects and patients with neoplasms. A simple peptide model is employed in the structure-function studies of hormones. Specifically, evidence has been accumulated to indicate the presence of human chorionic gonadotropin (hCG) or hCG-like substance distinct from the luteinizing hormone in the pituitary glands and in urines collected during the late luteal phase from women receiving contraceptive measures. A simple and effective analytical method to detect alteration of hCG glycosylation in toxemia patient was developed, and the dominant role of carbohydrate structure in the 8-subunit of hCG was elucidated. Finally, a series of sigma-opiate receptor specific enkephalin peptides were synthesized.